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Mercedes 300 Adenauer Review (1953 – 1962)

Overall Summary

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Overall Summary

The Mercedes-Benz S-Class of today is what we might call the very top of the industry in terms of style, class, performance and innovation. It is a flagship model of one of the most esteemed car manufacturers in the world. The 300 Adenauer was the same thing back in the 1950s. All the best in high-class automotive engineering effectively designed into one car.

The first 300 Adenauer came into production in 1951. It incorporated the best features known to the company at the time, such as the X-frame chassis, as well as some completely new features such as the 3 l, overhead cam, inline 6 engine. The result was a car that proudly held its own in terms of luxury with the likes of the Rolls-Royce Silver Cloud, but confidently surpassed it in terms of performance.

Moreover, there were numerous body styles available. Apart from the standard four-door saloon and two-door convertible, there were also four-door phaetons convertibles and long wheelbase limousines, as well as two-door coupes and convertibles. Excluding the special models, the hand-built two-door tourers were the very top of elegance and class.

Luxury was expected, since the car was aimed towards affluent businessmen and high-stature politicians (the car actually got its people’s name Adenauer from the fact that the first Chancellor of the Federal Republic of Germany Konrad Adenauer used six of these cars customized to include even things like desks, sunroofs, dividing partitions for the interior and curtains), so knowing that the car packed optional features like VHF mobile phone and a dictation machine is rather an exercise in domination by Mercedes than a surprise.

The 300 in the name stood for engine size. It was a M186 3 l SOHC, inline 6-cylinder with two Solex carburetors and several innovative design features that resulted in 115 hp (125 hp in a later version, 150 hp and 175 hp in W188 and 180 hp in direct injection 300d with the M189 engine from the 300 SL). This kind of a power meant that the car was not meant to be used as a racing machine, but rather to provide the owner with unprecedented reliability, involving features like tougher crankshaft, copper-lead bearings and oil cooling administered using a thermostat. All these features in a disburdened engine meant that it could literally cruise at its top speed nonstop.

The W186 was the first of the Adenauer Mercedeses. It came in 1951 as a four door machine named Type 300. It was an instant hit with the rich and famous for its style and plush features, but the X-frame chassis and innovative suspension made it incredibly agile for a car of that size and weight.

The W186 got its first revamp in 1954 in the form of the 300b. It came with better brakes and more power coming from new carburetors and higher compression ratio.

A year later the W186 300c came sporting some styling alterations and an optional 3-speed automatic gearbox. It was produced until 1957 when it was replaced by the W189, also called 300d (not to be confused with the later 300D six-cylinder diesels – this was still a 3 l gasoline engine powered car).

The W189 was longer than the previous model, it had a new hardtop design solution and it employed the revolutionary direct fuel injection system also used in the beastly 300 SL. This is the main reason for its 180 hp power rating. The automatic gearbox became a standard feature, while power brakes, air conditioning and power steering were optional.

The W188, also called 300 S came a few months after the W186 and it came in the form of a hand-built two-door car as a roadster, coupe or convertible. It was significantly more expensive than the W186 and the absolute top of the offer at the time. Additionally, it had an extra carburetor and higher compression ratio which gave it 150 hp.

In 1955, the W188 received a very significant revamp (dubbed 300 Sc), despite the fact that it had just a slight styling difference in the form of a pair of neatly placed chrome strips. The significance came from the fact that it included 300 SL’s direct fuel injection for even more power and low-pivot independent suspension for the rear.

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Driving & Performance

Many people today say that the S-Class is not a car to drive, but one to be driven in. Although I would beg to differ, the 300 Adenauer might be the perfect example of the back-seat passenger’s enjoyment. The simple fact that the wheelbase kept increasing over time, providing more and more room at the back, is enough to show us the real purpose of the car.

The same goes for various amenities that were optional or standard. In terms of riding comfort, independent suspension did wonders, especially having in mind the weight of the car. However, even though the car was geared towards comfort, it cornered better than its competitors. Don’t expect any track performance from it, even by 1950s’ standards, but looking at a car of such size would make you think that it handles far worse than it does.

As time went by, drum brakes became better (vacuum assisted power brakes from 1954) and power steering became an option in 1957, which is highly recommended if you are driving at lower speeds.

The first model, the 300a had 115 hp and the top speed of 96 mph. The only transmission option was a 4-speed manual.

The model marked 300b also fell under W186 chassis code and it brought a slight power increase to 125 hp which, having in mind more than 3,900 lb of weight, upped the top speed by only 3 mph to 99 mph and dropped acceleration to 62 mph by one second to 17. However, power brakes became available after this model and this improved drivers’ confidence with such a large machine.

The 300c came in 1955, having the same performance figures, but introducing an automatic gearbox as an option.

The W189 came in 1957 and it was called 300d. With 180 hp coming from mechanical fuel injection system by Bosch it might seem like a big boost in performance, but in fact, the top speed and acceleration were only a little better due to the, then standard, 3-speed automatic transmission.

The sportiest versions of the car were surely the two two-door models – 300 S and 300 Sc. The first one had 150 hp and the top speed of 109 mph, while the direct injection Sc model had 175 hp which was good enough or the top speed of 112 mph and acceleration to 62 mph of just 14 s.

All of the versions had one thing in common. They were all absolutely over-engineered and capable of running at top speed for days on end. This is also where they felt best. The Adenauer Mercedes-Benz is still one of the best cars for relaxed highway cruising.

Equipment & Comfort

Once again, this was the absolute top of the lineup in terms of comfort, so all the materials were top notch. The seats were plush and covered with leather. They did not provide lots of side support, but this was understandable, having in mind that the car was not meant to be driven harshly and that comfort was the first thing on the designers’ mind. Speaking of comfort, they were absolutely perfect. Large, soft, accommodating, comfortable and very durable, so many of them still look and feel as new.

There was enough room for everyone on board. However, some versions had incredibly long wheelbases, thus providing their owners with space and sometimes even features otherwise found in lush living rooms. Some later cars had optional air conditioning.

There was no central console at the front, so the two front seats were very close to each other. However, they were so big that there was no worry that the two people sitting at the front would be too close. The dashboard was covered in fine wood with a chrome strip at the bottom. The strip held a number of knobs at the driver’s side and two air vents in the middle.

The instrument cluster was dominated by a large circular speedometer surrounded at the bottom by a panel holding four small rectangular instruments. The middle of the dashboard, right above the central air vents, was reserved for the radio and, above it, a stylishly designed analog clock. In front of the passenger there was a big glove compartment.

Running Costs

Parts can’t be called cheap, but they do last forever. Many of the more expensive ones fall into lower three-figure territory, but there are some which go well into thousands, such as the rear axle drive pinion which stands at about $1,800. The front suspension tie rod costs about $700 and the front shock absorber for the first model will set you back about $300.

However, all these parts are well worth the money. They are built so well that they greatly surpass the needed toughness, so investing into high quality parts probably means that you are replacing them for the last time.

History & Development

History of the Mercedes-Benz Type 300 Adenauer starts in April 1951 at the Frankfurt Motor Show. At the time the styling was very modern and having it in the forms of a saloon and convertible made it even more exclusive. It featured the X-frame chassis, already familiar from some previous models, but also a completely new 3 l SOHC I6 engine with tow Solex carburetors. It was a work of art, well able to sustain absolutely anything a driver would put it against, be it walking-speed parade driving, or high-speed highway cruising.

Suspension was independent on all four wheels with stabilizer bar, double wishbones and coil springs for the front and double coil spring swing axle for the rear.

The 300b came in March 1954 with just a few changes. First of all, power brakes appeared, as well as vent windows for the front doors. However, the most notable change is the power increase of 10 hp which came from updated Solex carburetors and an increase in compression ratio.

The 1955 300c, on the other hand, was a far more comprehensive revamp. Apart from slight styling changes such as a bigger rear window, this was also the first model which offered a 3-speed automatic gearbox as an optional feature. Another first is the appearance of the Type 300 Lang, which had almost 8” longer wheelbase compared to the regular model.

Together with the W186, the two-door W188 (300S) was produced. It was a classier, more expensive version of the car and it came in three forms – roadster, coupe and landau-bars convertible. All of them were hand-made, which made it more extravagant than the W188, also commanding a significantly higher price.

The engine was the same, but the W188’s first version had three Solex carburetors and higher compression ratio, so the same engine boasted 150 hp.

The second iteration of the W188 (300Sc) came in 1955 and brought several engineering changes. The most notable one came from the legendary 300 SL – direct fuel injection. It boosted the power rating to 175 hp, making this car the fastest one of all the models connected to the Adenauer models. Another peculiarity of the revamped 300Sc was the low-pivot independent suspension for the rear. On the outside, if you were aiming to distinguish the 300Sc from the previous 300S, you could only rely on two chrome strips on the sides of the hood.

1957 bought the biggest facelift of the Adenauer in the form of the W189. It was longer than the W186, boasting 4” longer wheelbase; it featured mechanical Bosch direct fuel injection and it magnificently lost the middle pillar, which was perfect for parade driving. Power rating rose to 180 hp, but new standard 3-speed automatic gearbox kept the performance figures close to the previous model.